The Core Laboratory will be directed by an experienced postdoctoral fellow. Dr. Jincun Zhao, under the guidance of the Core Leader, Dr. Perlman. The Core will be primarily based in a BSL3 laboratory that is equipped for tissue culture and animal work. Personnel working in the Core are experienced in virological and cell culture techniques. The Animal Core has several functions that are critical for success of this POl grant. It will propagate and titer nonrecombinant and recombinant mouse-adapted and Urbani strains of SARS-CoV and will infect mice with these viruses. It will monitor mice for clinical disease and weight loss and will harvest tissue. The Core will prepare samples for histological and immunohistochemical analysis and will prepare RNA and protein from infected tissue. The Core will analyze mice for antibody and T cell responses. The Core will also be responsible for ensuring that protocols for working with animals and for working under BSL3 laboratory conditions are up-to-date. While the Core will teach members of the Project methods important for analysis of mice under BSL3 conditions, it will primarily be responsible for performing most of these analyses. The Core will provide reagents and perform common assays efficiently, thereby standardizing results and enhancing synergistic interactions. Additionally, all projects will interact with the Core, thereby facilitating interactions between members of the PPG. By providng these services, the Core will allow Program investigators to focus on issues related to SARS-CoV pathogenesis and to the development of anti-viral therapies and vaccines.